We’re working hard on balancing and testing Diablo III, and one of the major components is making sure that the end game experience is fun and exciting. We’d like to share a few of our goals for end game:

We have an enormous number of skill build combinations, and we want a lot of those skill builds to be viable and interesting
While there are millions of skill builds available to players, we don’t want players swapping skills regularly to beat specific encounters as they come up
We don’t want repeatedly running specific three-minute chunks of the game to be the most efficient way to acquire gear for your character
While a three-minute run shouldn’t be the most efficient, we also don’t want you to feel like it’s a two-hour commitment every time you sit down to play
Bosses should still feel worth killing

Nephalem Valor is one of the major new systems in Diablo III and it kicks in at level 60. Keep in mind that this is still in testing and we’re still working out the details. Here’s how it currently works internally: Rare and Champion packs already have great loot on them. By killing a Rare or Champion pack, not only do you get their loot, but you’ll also receive a buff granting you increased magic find and gold find. However, if you change a skill, skill rune, passive, or leave the game, the buff disappears. As an extra reward, if you kill a boss while this buff is active, you’ll receive extra loot drops from that boss.

The exact amount of magic find and gold find provided by the buff is still being reviewed, as is the amount of extra loot you get from a boss while the buff is active. We’re also playing around with whether or not the buff stacks, what the duration should be, and whether or not it should persist through death. We want to make sure the buff is strong enough to make staying in your current game more rewarding than creating a new game. At the same time, if the buff is too strong, it risks making shorter play sessions feel not worthwhile.

We expect this system will encourage players to stick with a skill build of their choice, select an area of the game they enjoy, and sweep it for rare and champion packs on their way to a boss, finishing off a run with a boss that’ll be worth killing. If you wanted a shorter play session you could be done at that point, but if you have more time, the path of least resistance would ideally be to stay in the same game and make your way towards the next boss.